The three-time champion and the Thai 38th seed, who came through qualifying and stunned Shaun Murphy, went into Friday's afternoon session with the score finely poised at 8-8 and it continued as a tight affair.
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The Jester from Leicester edged in front with a sensible frame before Noppon responded in style, taking the next two frames.
First he registered a break of 54, sending home the pink, before showing true grit to grind out Frame 19 which lasted 50 minutes by taking it 73-39.
Selby quickly got back into it, though, as he recovered with a break of 77 heading into the final interval.
The 37-year-old made it back-to-back frames after the restart with a break of 75 and raised his game.
Under extreme pressure he put himself on the cusp of a place in the quarter-finals with an impressive 92 clearance.
Noppon kept his hopes alive by winning the 23rd frame 68-19 and then showed nerves of steel with a terrific break of 90 to force a final-frame decider.
Selby showed his experience in the decider though, taking it with a 124 clearance, and will face the winner of Neil Robertson vs Barry Hawkins in the quarter-finals.
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